Railboad-cab axle



UNITED STATES FATENT OFFICE.

JAMES MONTGOMERY, OF BALTIMORE, MARYLAND.

RAILROAD-CAR AXLE.

Specification of Letters Patent No. 28,004, dated April 24, 1860.

To all whom 'it may concern.'

Be it known that I, JAMES MONTGOMERY, of the city and county of Baltimore and St-ate of Maryland, have invented new and useful improvements in my patented shaft for steam machinery for railroad-axles and for all similar purposes in which axles are employed I design the axle or shaft hereafter described; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming part of this specification.

Figure l is a side elevation of a railroad axle, constructed after my patented method, with the additional improvement attached. Fig. 2 is a vertical section of the same at the line 1, 2, of Fig. 1. Fig. 3 is a vertical section through the journal of the `same and the box in which it rests at the line 3, 4, of Fig. 4. Fig. l is a vertical longitudinal section through the center of the said axle and journals. Fig. 5 is a longitudinal section of a modification of the improved compound hollow shaft, with the journal thimbles or sleeves represented outside the wheel hubs. Fig. 6 is a vertical transverse section of the same. Fig. 7 shows a modification of the hollow axle I propose for a steam boat shaft and Fig. 8 is a face view of the crank.

Similar letters in the figures refer to corresponding parts.

To enable others skilled in the art to make and use my improvements, I will proceed to describe the construction and operation of the same.

The improved compound railroad car shaft is composed of a series of wrought iron segmental and stave shaped bars A, so rolled by peculiarly formed rollers as to form when placed and secured together, in the manner hereafter stated, a hollow compound shaft, whosebearing ends shall be of a cylindrical shape, and the part between, swelled to a greater diameter as it approaches a point midway between the ends.

The edges of the bars A, at the cylindrical parts are parallel, so as to enable them to be brought flush with each other at these parts, are held firmly together by steel thimbles or sleeves B, having corrugations on their inner peripheries, and placed in their proper positions on the cylindrical portions while in a heated state, and cooling and shrinking thereon so as to firmly hold the said end parts together. These bars A,

are made of greater thickness at the bearing portions than at the center. Between the ends, their thickness being reduced nearly one half, and as they bulge or swell outward in their approach tothe said center they gradually increase in width, so as to leave narrow spaces or slots C, between their edges, which spaces or slots taper from the center to points at the inner edges of the steel thimbles or sleeves B. These bars A, are strengthened and prevented from vibrating at the points midway between the wedge shaped ends of the slots or spaces C, by means of a plug thimble D, acting conjointly with the form of the swelled bars to produce the result named. This thimble D, consists of a hub or ring of wrought iron or other material, exactly fitting within the bars A, when put together to form the shaft, and inserted therein before being thus formed into the shaft, around which and the outside of the bars and in the enlarged parts of the slots between the same, is cast the outer portion, so as to enable the cast metal to firmly connect itself to the several parts with which it is in contact, and thus produce the same solidity as if the several distinct connecting parts were one cast, fused or welded body of metal. I sometimes propose to use a simple thimble bush held firmly to its place by the pressure of the barsonly. The corrugations or flutes on the inner peripheries of the steel thimbles or sleeves B, extend from one of their edges to the other, so as to form when placed upon the shaft, openings between the shaft and thimbles, extending entirely from one edge to the other for admitting the free circulation of air through said openings and the consequent carrying off of the heat produced by the friction of the journals, thereby ena bling the said steel thimbles or sleeves B, to be kept cool. A series of openings E, are also formed around the bearing portions of the boxes F, a short distance from the peripheries of the same, which openings extend entirely through the boxes, and thus admit the free ingress and egress of cool and heated air respectively, for the same purpose and in much the same manner, as the openings betweeen the axle and thimbles or sleeves B.

On the peripheries ofv the outer ends of the shaft, are cast circular or other shaped j shoulders G, of malleable iron or other metal, which slightly taper on their pelOO ripheries to admit the bosses or hubs of the car wheels being fitted and secured over the same, and also serve to firmly hold the cylindrical ends of the shafts together.

The swelled bars A, which compose the shaft are rolled and put together in the folk lowing manner. The rollers between which they pass are secured in frames and boxes in the usual manner, and are in diameter equal to about one third the length of the bars to be rolled Concave channels or indentations, resembling the scotia molding in architecture, are formed in one of the rolls and in the other a corresponding indentation, somewhat resembling the torns molding, with angular ridges or shoulders at its edges, which indentations when brought together respectively correspond with the outer and inner convex and concave surfaces and radial edges of the bars A, the width and depth of the said indentations beyond the cylindrical peripheries of the rollers, for a certain distance, being uniform so as to roll the said bars to one corresponding uniform thickness and width the required length to form the cylindrical portion of the journal and the wheel. Thence the indentations are to go on gradually increasing in width, but decreasing in depth, until they reach points of the peripheries corresponding with points situated midway between the ends of the bars, and of course midway between the ends of the axle, where their depth must be such as to give about one third less volume of metalto the bars at this part than at the cylindrical portion. From these points the indentations gradually contract in width in their course around the peripheries of the rollers, and again increase in depth until they reach the points where their depth and width continues uniform, to form the segmental ends, which, when put together, form the cylindrical portion for the reception of the journal thimble or sleeve B, and cast shoulder G, at the end over which the car wheel hub or boss is secured.

The bars A, thus rolledfare formed into a shaft in the following manner. A sufficient number of them to constitute one half the shaft, are placed with their edges together, and in the proper positions they are to occupy in relation to each other, in a mold or frame of the required form and size to hold them together temporarily, and the inner wrought iron portion of the plug thimble,

having a circular opening through its center, is placed within the bars in the required position, and the other bars composing the shaft are properly built over the same, and the whole series are firmly clamped together by suitable grippers or tongs. The flanged steel thimbles or sleeves B, are then moved over the ends of the bars A, in a heated state, and are allowed to cool and shrink upon them over the cylindrical portions, im-

mediately next the points where the swell of the bars commence. A mold is then formed around the inner portion of the plug thimble D, and the largest portion of the bundle of bars A, and around the peripheries of the extreme end of the same, and the cast malleable, or other metal, is poured into the said molds, and made to thoroughly embrace and connect itself with the parts which Yit surrounds and with which it is in contact, and complete the plug thimble D, and form the shoulder Gr, upon which the hubs or bosses of the car wheels are secured.

I propose sometimes to cast the car wheel directly upon the ends of the axles, thereby saving the cost of boring and fitting the wheel to the axle, and at the same time effecting the object desired, but I am well satised that the method described of accomplishing this object will be found far preferable.

The form of these bars A, may be varied to correspond with the character of the shaft intended to be made, the main characteristic of having tapering slots C, between the parts around which the journal thimbles or sleeves B, are to be secured, being observed, as for example, when it is desired to make a steamboat wheel shaft, to one end of which a single wheel is to be attached, and to the opposite end a crank or other device through which the motive power is applied. In this case the outer surfaces or peripheries of the bars are made of a segmental form of the same uniform external diameter, and from points situated the required distance from the crank, or at the end where the motive power is first applied to admit the journal thimble or sleeve and crank, to the extreme opposite end, a slight taper is given the said bars in width, while from the said motive power end to the opposite one, they are gradually and uniformly reduced in thickness, so as to enable the tapering slots between them, when brought together to form a shaft, to commence at nothing and gradually increase in width to the opposite end, where their maximum width is one eighth to one fourth of an inch, and the bore or hollow of the shaft they form to gradually and uniformly enlarge in diameter from the said motive power end to the opposite one from which it is to be transmitted, in such a manner as to reduce the bulk or volume of metal at this latter end, in the same proportionate degree as the railroad axle before described. In this case the journal thimbles or sleeves B, are shrunk on in the same manner as they are in the railroad axle described, and the thimble plu D, is cast around and between the ends o the bars A, the hollow tapering wrought iron thimble plug D, being first inserted within them so as to enable the cast metal to connect itself with it and the ends of the bars A, thus preventing the thimbles from moving oli', as Would likely be the oase were this process not observed.

A single one only at the central portion, as represented in Fig. 1, tvvo, as represented in Fig. 3, or any desired number may be attached.

The steel journal thimbles or sleeves B, may be either shrunk on the ends of the aXles, in the proper relative positions, with the ends they are to occupy` to form journals, or they may be driven and keyed on While cool, the portions Which they embrace being made slightly tapering or not, and they may be either arranged inside or outside the Wheel bosses as desired, and can when cut or otherwise Worn out and rendered useless, be removed and replaced by others.

An additional security toward holding the thimbles or sleeves B, in their proper positions at the ends of the shaft when they are arranged to form outside bearings, may be obtained by riveting or upsetting the ends of the Wrought iron bars A, forming the shaft, over the outside edges of the thimbles or sleeves B.

In case it is desired, the Wrought iron bars A, may taper from their longitudinal center portion to the eXtreme ends, and dovetail Wedge shaped pieces of steel S, may be driven in between them at their ends, immediately inside Where the cast hubs G, and journal sleeves or thimbles B, surround them, in Which event the said steel Wedges Will be held in their places, by their peculiar dovetailed sides, acting against the radial edges of the bars, and by keys or pieces at their inner ends, as represented.

What I claim as my invention and desire to secure by Letters Patent, is-

l. A shaft or axle constructed substantially as described.

2. In combination with the same a central brace or braces D, movable journal thimble B, and cast iron hub, constructed substantially as herein set forth.

3. The openings E,between the circumference of the axle and the thilnble journal B, and through the body of the metal composing the journal boX substantially as and for the purposes set forth.

JAMES MONTGOMERY.

Witnesses WM. TUscH, IV. HAUFF. 

